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The 21st Annual American Mining Hall of Fame Awards Banquet sponsored by the Mining Foundation of the Southwest will be held at the Sheraton Tucson Hotel in Tucson, AZ on Saturday, Dec. 6, 2003. This year’s inductee, guest of honor and featured speaker at the banquet will be Thomas J. O’Neil, recently retired president and chief operating officer of Cleveland Cliffs Mining. Prior to Cliffs, O’Neil spent 10 years with Cyprus Minerals. He was also professor and head of the Department of Mining and Geological Engineering at the University of Arizona. As representatives of mining heritage, the Hall of Fame will induct James Boyd and Thomas F. Walsh. Walsh discovered a rich gold telluride vein in Ouray, CO, which became the Camp Bird gold mine. Boyd was a former director of the U.S. Bureau of Mines, vice president of Kennecott Copper and later president of Copper Range.

Jan 1, 2003

By Jennifer Pell

Dunsmuir Ventures? Nanuq diamond project is located approximately 250 km northeast of Baker Lake and 170 km north of Chesterfield Inlet. It occurs at the intersection of the Wager Bay shear zone with the Keewatin Arch, a major long-lived crustal uplift. The newly discovered diamondiferous kimberlites at Rankin Inlet, Repulse Bay and on Melville Peninsula also occur along this arch. Kimberlite indicator mineral (KIM) sampling has outlined a distinct KIM train more than 35 km long and 6 km wide. Geomorphological studies, boulder displacements and dispersion of magnetite in tills suggest that glacial transport distances were on the order of 4 to 6 kms only. The presence of multiple sources within the main Nanuq indicator train would account for its length and breadth. A second train has been located on the west central part of the property and anomalous concentrations of KIM occur elsewhere. Pyrope garnets (G9?s and G10?s), diamond inclusion field (DI) eclogitic garnets and DI chromites were confirmed by microprobe analyses. Clinopyroxene thermobarometry indicates a cool geotherm, approximately 35 mW/m2, and that mantle within the diamond stability field was tapped. An aeromagnetic survey has identified a number of anomalies. Those with down ice KIM support will have ground geophysical follow-up and will be tested in a spring 2004 drill program. Dunsmuir is optimistic that this will lead to the discovery of a new kimberlite cluster on the Nanuq property.

May 1, 2004

By A. A. Debrah

Artisanal and small-scale mining (ASM) plays a fundamental role in the national and local economies of resource-rich countries in Africa. As such, more effort must be geared towards fostering this type of economic activity to sustain livelihoods in rural communities. Across Africa, efforts to operationalize ASM based on a sustainable development framework have been quite tedious and often ineffective. This is because most of these frameworks lacked context and an understanding of the continuum from the artisanal through small-scale and up to the junior miner, grouped under the general term ?ASM?. Driven by the need to contextualize some of the definitional issues in this niche sector, and gain a clearer understanding of their peculiar challenges, this paper aims to contribute to the debate on ASM by considering two of Africa?s resource-rich countries ? Ghana and South Africa. Since South Africa has made greater inroads in protecting the interests of small-scale miners, we thus draw comparisons from both countries? approach to ASM, outline the lessons learnt, and provide recommendations regarding the ways forward.

Jan 1, 2014

By John C. Stankus

Jennmar Corporation. in an effort to improve mine roof control, has conducted extensive study and research comparing tensioned point anchor resin systems versus the use of non-tensioned fully grouted rehar. Preliminary indications are showing that in thinly laminated, weak strata, tensioned point anchor resin systems are providing more effective roof control than the non-tensioned fully grouted rehar. In this paper two case studies are presented in which tensioned point anchor resin systems were utilized to stabilize and control the mine roof in two different mines. Both mines are alike in many ways, but yet very different in other aspects. However, the mines do share one main common factor. and that being the non-effectiveness of the non-tensioned fully grouted rebar in controlling the thinly lamininated strata in each respective mine.

Jan 1, 1990

By Larry Stearns, Lori Tiefenthaler

Remediation of contaminated soil represents a significant market for application of Deep Soil Mixing (DSM). Eighty-one percent of U.S. Environmental Protection Agency (EPA) Superfund Program’s site remedies have involved contaminated soil. Contaminated soil is frequently treated by In-situ Solidification/Stabilization (ISS). ISS treatment of contaminated soil involves mixing binding agents into soil using DSM techniques. DSM is a core business for many DFI members. Members may improve and broaden their services to clients by learning about the recent ISS treatment of contaminated soil at a Superfund site. ISS treatment is part of the EPA-selected remedy for a Superfund Site in the metro New York City area. The property has seen heavy industrial use for more than a century. Soil at the site is contaminated with a variety of volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs) including coal tars and heavy metals, principally arsenic and lead. Beginning in 2017 and continuing through 2018, approximately 150,000 cubic yards (115,000 cubic meters) of soil will be treated by ISS at the case study site. Portland cement and slag cement are mixed into the soil by DSM techniques using GPS guided excavators to immobilize the hazardous constituents within the treated soil. ISS treatment by DSM will contribute to redevelopment of this valuable property. This paper will describe ISS constructability and performance, case study grout mix design with geotechnical results for strength and permeability, and deep soil mixing techniques. INTRODUCTION In-situ solidification and stabilization (ISS) is a deep soil mixing (DSM) technique applied in the environmental remediation field to physically encapsulate, or chemically bind, contaminates of concern such that the impacts to human health and the environment are mitigated. Common remediation applications of ISS include mixing cementitious reagents into contaminated soils to form a monolithic mass with desired performance characteristics, and the installation of vertical subsurface walls designed to control groundwater movement. A key characteristic of ISS is that the contaminated soils are treated in their existing location at the project site and then are left in place after treatment. Typical performance characteristics of the ISS treated soils include improved unconfined compressive strength (UCS), reduced hydraulic conductivity (HC), and reduced leaching potential of soil contaminants. Increased shear resistance of the treated soil may also be a performance requirement where seismic loading is a concern.

Jan 1, 2018

By Northcutt Ely

This volume summarizes mining and petroleum legislation in 45 African jurisdictions. Within these jurisdictions, primary attention is given to requirements that must be met in each country for acquisition of rights to permit development of mineral resources. Coverage includes: First, identification of the controlling laws or statutes governing minerals acquisition and reference to the administrative authority; second, analysis of the laws governing mines and quarries and their products; third, analysis of laws applicable to natural gas, petroleum, and related materials; and fourth, mention of laws regulating offshore operations. Where pertinent, sections dealing with historical background or administration have been added. In countries where minerals are subject to control of states or provinces, those areas are considered separately from the central government.

Jan 1, 1974

By Frank Rausche

Since the early 1980s, when the Road Construction Authority of Victoria authorized the dynamic proof testing of roughly 100 drilled shafts of 1.5 m diameter and typically 60 m length in Melbourne Australia, dynamic load testing has been applied worldwide for quality control of drilled shafts. Today, test capacities of 4000 tons or more are not unusual. On numerous occasions the authors have been involved in similar tests in the United States and test engineers from other countries have reported on experiences in many different countries. Without doubt, generating high test loads is most economically accomplished by dynamic load testing and this method is particularly well suited for testing piles founded in rock because of the rocks low energy dissipation. However, deep foundation professionals have on occasion expressed reservations about subjecting a drilled shaft to impact loadings fearing, for example, a degradation of the shaft ? rock interface properties or potential error sources due to uncertain concrete properties or shaft geometry. This paper will present numerous case studies, demonstrating the performance of rock socketed drilled shafts under dynamic loads. It will discuss the mechanics of the dynamic tests and the method of data interpretation, addressing the concerns stated above and investigating the limitations of the test method. The paper will formulate a set of recommendations for the design and execution of these tests.

Jan 1, 2006

By Bradford F. Townsend

A study was made on six collapses that occurred during large-diameter tunnelling through weak sedimentary rocks and soil using SES methods in three stages?top heading, bench and invert. The collapsed lengths are between 20 m and 277 m. The collapses were re-mined using essentially the same tunnel-ling method with larger excavation profiles to accommodate the designed remedial measures consisting of ground treatment, pre-support and stronger initial support/outer lining required to carry higher ground loads acting in the collapsed lengths. The paper presents information on the collapses and the design and execution of the remedial measures.

Jan 1, 2008

By José Carlos do Amaral, Marcelo Groszownik, Jorge Beim

"Initiated in 2008, the project of this 1800 km long Electrical Transmission Line is a job of extreme technical complexity, crossing regions of major forests and rivers. When ready, it will allow the large Brazilian states of Amazonas, Amapá and Pará to use the energy from hydroelectric plants, thus eliminating the need for the use of diesel fuel thermal plants, with their much larger environmental footprint. Due to its extraordinary characteristics, the Green Peace and the Discovery Channel constantly visited the job. The part between the Amazon and the Xingu rivers started in 2012, and encompassed about 100 transmission towers with up to 150 m height, through a region known as “Alagados”. This region exhibits a 1.5 m water level during the rainy season, and soaked ground the rest of the year. Navigation of regular vessels is impossible during the flood season, when a dense vegetation called “bulhado” fills the riverbed, and vehicle traffic is impossible during the dry season, due to the extremely low surface soil resistance. Great logistical and technical difficulties were encountered for driving and determining the capacity of the piles. New systems had to be developed for driving the piles, with the simultaneous use of 15 small piling rigs. The final penetration, total number of hammer blows during driving, plus Dynamic and Static Load Tests were used for determining the driving and acceptance criteria.The geographical challenge and initial conditionsThis paper describes the execution of foundations for a 500 kV Electrical Transmission Line in a region that becomes flooded during the rainy season and heavily muddy during the dry season. This is the monsoon climate, typical of the equatorial region of Brazil, where there is a rainy season lasting for about half the year, followed by a very dry season. The temperature varies very little throughout the year, due to the proximity to the equator. The locals call the rainy season “winter” and the dry season “summer”.The most important part of the so-called “Alagados” region is situated inside an Environmental Extractive Reserve (RESEX) called “Verde para Sempre” (Forever Green), created in 2003. This is one of the largest environmental reserves in Brazil. It is an area controlled by the Brazilian Environmental Control Department, the Chico Mendes Institute (ICMBio). The environment control parameters are very strict.No deep foundation had ever been executed before along the “Alagados” region. The main challenge faced on this job, however, was working in a place where self-propelling vessels or land vehicles and equipment cannot be used. During the rainy season there is a dense and intricate vegetation called “bulhado”, which prevents the movement of outboard motor boats with propellers going deeper than 50 cm. In the dry season, the heavy mud prevents the movement of foundation equipment, excavators, trucks and other machinery."

Jan 1, 2015

By H. R. Shell

The work on synthetic mica and related subjects is being reported in a series of technical articles (see Supplementary Bibliography), each of which describes some special aspect of the subject. This is the final report on chemical analysis of the fluoride-containing silicates. A condensation of this report has been published (26).3/ Chemical analysis affords one of the best means of ascertaining the final com-position of either a heterogeneous mass or a single pure crystal, particularly where some constituents may be volatile. The analysis of fluoride-containing silicates was not so well known or understood that highly accurate results were commonplace. For example, on synthetic mica a university laboratory reported 11.6 and 9.2 percent fluoride when at least 13.3 and 11.3 percent were present, respectively; a commercial testing laboratory reported 9.14 percent as compared to 12.6 percent; and a glass company reported 7.0 percent as compared to 9.0 percent present. No intimation is made that these analysts could not have done better, but the point to be stressed is that the methods in use were long, tedious, and generally required a certain familiarity for best results.

Jan 1, 1956

By Sam Palombo, James José Varela

"Washing can be defined as the process used to eliminate or reduce the dirt (presence of fines or slimes) of one material. It is also the basic and oldest process applied to ore preparation for further concentration. This process, in combination with commnution and screening, form the so called washing plant and in many cases produce end products. This work describes the factors that influence the performance of the washing process and main washing technologies used in the mineral processing industry.The Hydro-Clean represents, since 1998, a state of the art technology in this area and is comprised of one of the most innovative solutions developed at HAVER & BOECKER. HAVER & BOECKER design and manufacture technology for mining and related industries. Today the Hydro-Clean is manufactured and sold throughout the Haver Screening Group (HSG) which is comprised of HAVER & BOECKER Maschinenfabrik Münster, HAVER & BOECKER Latinoamericana – Brazil and W.S. Tyler Canada.The Hydro-Clean is a washing technology based on utilization of high pressure water jets. To follow we will discuss how the Hydro-Clean’s different modes of operation result in several advantages related with mine waste reduction, recovery of saleable product, lower capital costs, superior washing results, less stress for the material, a wider range of application and less maintenance cost. Aside from these positive factors, its lower operation costs related to the consumption of energy and water are presented. It is important to note that the quantities, tonnages, data and management concepts presented in the paper are accurate for the time of writing and are subject to change and modification as operations progress."

Jan 1, 2009

The University of New South Wales (UNSW Australia) has been a world leader in the development of innovative virtual reality technologies over the last 15 years. AVIE (Advanced Visualisation and Interactive Environment) was developed by iCinema as a collaborative venture between UNSW?s Faculties of Engineering and the College of Fine Arts. This is the world?s first 360°-surround, virtual reality (VR) stereo projection theatre system. The School of Mining Engineering at UNSW Australia has developed 18 different virtual reality modules aimed at mine safety training and mining engineering education. These modules are being regularly used in both the mining industry and the university. The School of Mining Engineering is continuously involved in the development of different modules. Research is also currently being conducted on the implementation of other technologies into this environment. Artificial intelligence (AI) and fuzzy logic are tools that the authors would like to consider implementing in future module development. This paper will review current research in both these areas and consider options for applying these technologies.

Jan 1, 2014

By L. A. Matthews

The embrittlement of the Ti-6Al-4V alloy by hydrogen dosing at elevated temperature has been investigated. Metal coupons were subjected to isothermal treatments in a partial hydrogen atmosphere in the temperature range from 650ºC?950ºC and the degree of embrittlement after treatment was determined by drop-weight impact testing. Embrittlement was found to be inversely related to reaction temperature as a result of the combined effects of greater hydrogen absorption and titanium hydride precipitation at the lower isothermal temperatures. Keywords Titanium, hydrogen embrittlement, impact energy

Jan 1, 2011

By Warren L. J

The effectiveness of shear-flocculation as a method for upgrading simple mixtures of ultrafine (1-11 \lm) scheelite and garnet was evaluated. Statistical methods were used in the design and analysis of the main test program.The stirrer speed, stirring time, and initial weight ratio were all found to have significant effects on both the recovery and grade of the floes produced. The particle sizes also had an effect on the final grade. There were several important interactions between factors which also affected the results. Optimum conditions for shear-flocculation were established, and under these conditions about 80 per cent of the scheelite could be recovered at a grade which depended on the composition of the starting mixture. Starting with mixtures containing 10 and 50 per cent scheelite, the best final grades were between 20 and 50 per cent and between 70 and 90 per cent respectively, the actual value depending on the particular combination of particle sizes.

Jan 1, 1977

The Canadian mining industry is one of the strongest in the world. Not only does the country produce a sizable amount of minerals and metals, Canada plays host to hundreds of global mining companies, large and small. The country, for the most part, recognizes the importance of natural resource development, particularly mining, to its economic well being. Like any country, though, there are federal and provincial regulations on the books that the industry takes issue with. But there are also certain economic incentive programs in place to encourage exploration and mine investment. And, unlike the industry and the United States government, the Canadian government and mining industry appear to have a reasonable working relationship.

Jan 4, 2010

By A. G. Spencer

"The horsepower required to drive large grinding mills has increased dramatically during the past ten years. Limitations on the amount of power which may be transmitted by a single gear and pinion have resulted in the application of multimotor drives, with consequent loadsharing problems. It has also sparked the development of some entirely new drive concepts. In addition, the severe demands made upon the electrical system during the acceleration period have required that the selection of motors and electrical system design be closely coordinated. Moreover, the installation of such large process units results in downtime being very costly. The equipment selected and the plant maintenance philosophy must therefore be such as to minimize the risk of unscheduled downtime."

Jan 1, 1972

The results of self potential geophysical surveys conducted over base metal prospects near Orange, Goulburn, and Wellington, N.S.W., indicate that this rapid and inexpensive exploration procedure merits wider application within eastern New South Wales, and in similar environments elsewhere.

Jan 1, 1973

By E. H. T. Whitten

Fundamental principles of trend surface analysis are briefly reviewed. Recent analyses of several granite masses illustrate the method of estimating the quantitative regional composition and also variation trends. Mineralogi-cal, bulk chemical, and other quantitative variates can be employed. Such results should improve gravimetric surveys (etc.) relying on correction terms based upon estimated rock composition. For the first time realistic estimates of the mean composition of rock bodies can be made with the aid of trend components. Deviation maps hold promise for delimitation of disseminated mineralized areas. Deviations comprise residual "anomalies" after removal of trend components. In petrogenetic work such deviations have been shown to reflect local influences (e.g., contamination of magma by assimilation of xenoliths or country rocks of the envelope). Similarly, mineralization should be reflected as deviations standing out from background trends. Actual examples are given. Present results largely involved projection of data onto a horizontal plane, but if sufficient data are available use of three spatial coordinates increases accuracy for prediction in "unexposed" areas. Regression analysis shows that statistical correlations between variates for regionally distributed specimens are often strong (particularly with percentage data). Hence, in preliminary surveys more easily determined variates may sometimes be employed to gain first estimates of the distribution of components more economically significant. The sampling plan is of paramount importance. Unless a suitable sampling plan is devised and adhered to rigorously during collection of the samples, all subsequent analysis is liable to strong bias and to yield spurious estimates of the truth. For a wide variety of purposes it is becoming necessary to assess the quantitative composition and variability of rock masses and mineralized zones of various types. In petrology and petrography this is something of a break with tradition, because virtually all descriptions heretofore have been qualitative. Although vast amounts of qualitative data have been compiled, little is known about the quantitative behavior of rock components. However, if variability of rocks could be understood and expressed with sufficient accuracy, there would be considerable advantage to both economic and petrogenetic problems. For example, if, on the basis of a limited series of observations, the three-dimensional geometry of a disseminated orebody (or ore-bearing formation) could be predicted accurately, it would be possible to extrapolate with confidence the structure into unexposed areas. The following example based upon the geometry of an igneous cone sheet illustrates the point. The significant rock-unit gives outcrops at a number of points on the exposed surface ABCD (Fig. 1A). Study of n exposures may enable a geologist to predict that the rock-unit is circular in form and thus indicate where the unit can be expected in unexposed terrain. Such observations are made at sites with u, v coordinates, but, if subsurface information is available at sites with uvw coordinates, it will eventually become possible to predict accurately the three-dimensional form of the rock mass. Geologic rock masses or mineral deposits are not generally as regular and symmetrical in geometric form as the body illustrated in Fig. 1A. However, even where the broad limits of a major rock mass are known, a more acute problem arises in attempting to obtain detailed quantitative estimates of its internal variability; it is difficult to predict the variability of a mass from a limited number of observa-

Jan 1, 1961

It is easy to demonstrate the importance of aggregates in any conversation about infrastructure and other engineering artefacts. Peoples around the world have made use of stone to enrich and enhance their lives since the earliest days of civilisation. In New Zealand, Maori used hard durable rocks for weapons, tools, and basic structures. European settlement accelerated the use of quarried materials and formed the basis for development of our society as we see it today. Logic might suggest that the quarrying sector would be recognised positively for, and encouraged to continue to contribute to, this underpinning of the way we are. The reality is æNot In Most Back YardsÆ. Why? The rock is where it's always been (often overlooked) and our æsocialÆ environment is today's hard place. For a resource-based business in New Zealand, that environment is principally the Resource Management Act, with the widespread power it has distributed to anyone prepared to invest their time. This coupled with a lack of leadership and direction in the implementation of the Act has created a climate that stifles development and diverts energy and resources to æplaying the gameÆ rather than ælifting the gameÆ. Perhaps the real costs of this are not yet widely recognised. The paper will draw mainly on the experience of endeavouring to consent a ægreenfieldÆ quarry in the Waikato region. This is supported by commentary based on nearly 10 years of ælivingÆ with the RMA at sites across much of New Zealand. RMA Scorecard Summary: Effects based? Rarely. Level playing field? No. Maori Consultation? Could do better. Efficient use of resources? No. Timely? No. Is it working for other sectors? Certainly not the quarrying industry's customers and end users.

Jan 1, 2000

By G. Belzil, F. Robichaud, M. Fullam

"The Goldex mining and milling complex is operated by Agnico-Eagle Mines Ltd. and is located in the Abitibi greenstone belt of Northwest Quebec, Canada. The mill operates presently at a throughput of 8,250 tpd with gold grade varying between 1.8 and 2.2 g/t. The ore is very high in gravity recoverable gold (GRG) at about 92% and as such a significant emphasis was placed on the gravity circuit. Commercial production started in 2008. Average gold recovery is 93.5% with about 68% of gold recovery coming from the gravity circuit. Over the course of the first several years of production, several gravity audits were carried out. In 2009, a complete gravity audit was completed, including ore, classification, Knelson Concentrators, and the gold room. In 2011, an audit was undertaken of the flotation circuit to determine the efficiency by which GRG is floated. Large samples of flotation feed and tails were collected and process for GRG content. This allowed a link between gravity and overall recovery to be made. This paper presents results of the audits and the development of a model linking gravity and overall gold"

Jan 1, 2012